[Music] all right welcome back to another video lesson from ICU advantage alright so in this lesson here we're gonna continue our series here talking about ICU drips and in this lesson we're gonna begin our discussion talking about paralytics we're gonna specifically address what paralytics are as well as how they actually work within our patients body these are very powerful and potentially very dangerous medications that you are gonna come across in the care of your patients in the ICU so it's really important that you know what's going on with these so keep watching the lesson and I'm gonna do my best to explain it all to you before we get too far in though if this is your first time here to this channel and you'd be interested in watching more critical care educational content such as this video then I do invite you to subscribe to our channel below make sure you head down there and hit the bell notification icon that way as soon as our new lessons become available you'll be notified as always a special shout-out to our awesome subscribers you guys continually come back watch our videos like our videos comment on there all that stuff really goes a long way to help support this channel and for that I do want to thank you and my name is Eddie Watson and this is ICU advantage alright so let's go ahead and get into our lesson here we're gonna start off and talk about what are paralytics so our paralytics are also known by another name something that we call neuromuscular blocking agents and essentially what these medications are used for is to prevent the muscle contraction and so our neuromuscular blocking drugs or agents are what we call competitive antagonists and essentially what this means is that they're gonna bind Taurus II to choline receptors but not activate it and so by taking up these receptor sites this is going to prevent the actual neurotransmitter acetylcholine from activating that receptor site and therefore this is going to result in an inability for these muscles to contract so when we talk about these medications it's really important that we understand one thing and that is that they have no sedative amnesic and a steady or analgesic properties so this is important to know we are going to talk about this in a future lesson but all these medications are doing a simply preventing muscle contraction so now that we have a good understanding of the basics of what paralytics are let's really talk about why we would use them and when we look at these reasons on why we'd be using paralytics there are some short versus long term indications so one of the ways that most of us are probably going to be familiar with these medications is we often use them to help facilitate our endotracheal intubation and these medications are going to do this by relaxing the patient's jaw and their airway muscles making that easier in addition to that sometimes surgeries are gonna require muscle relaxation we may also look to use these to aid and giving us more accurate hemodynamic monitoring as well as if we're looking to assess what our patient's abdominal pressure is we're really gonna need our patients to be paralyzed in order to have a true accurate reading these paralytics can also be really beneficial in helping our patients compliance with the vent and really helping to reduce that ventilator de synchrony we've also found positive benefits in patients who have ARDS and this benefit is coming from really relaxing the patient's chest wall and ultimately reducing that intrathoracic pressure we're also gonna use paralytics and patients with high intracranial pressures as well as their use may also decrease our oxygen consumption and in addition to all this we'll also sometimes use paralytics to treat that refractory shivering and patients who are hypothermic so definitely a lot of different cases in which we could potentially be using these medications but I really want to stress though that we should only be using these medications when all other means to manage our patients have been tried without success alright so that way is a good foundation for what our paralytics and why we're going to be using these different medications in order to really better understand these medications though we have to dive in and talk about how it is that they work and this is going to require a little bit of anatomy and physiology and so to go through this there's really two different parts of this process that I want to talk about and so the first of these is to talk about our neuron action potential and so here we have a picture of a neuron and here you can see that long axon and the dendrite down there at the end and we kind of talked about action potentials in one of our previous lessons in this series where we are talking about our antiarrhythmic and so I'm gonna link to that lesson up above as well as down in the notes in case you haven't watched it because in that lesson we talked about an action potential and what it is but and so essentially when an action potential is is a brief reversal of this transmembrane voltage that we're gonna see across some sort of excitable membrane so in the case here the excitable membrane is going to be the membrane of the neuron cell and especially the axon and so when we look at these cells normally at rest they're going to be negative inside the cell and therefore positive outside of the cell and again this change in voltage is going to be a result of this electrolyte balance that we have we're gonna have sodium outside the cell and potassium inside our cell and so now what happens is if we have some electrical signal from the neuron body that reaches this threshold that this is gonna cause different sodium channels here to open up which is gonna allow that sodium to go inside of the cell creating a more positive charge in the cell and this is essentially what we call our depolarization and so now we're gonna see this depolarization in the beginning of the axon here but this is then gonna cause neighboring sodium channels to open up again allowing more sodium in down there changing the voltage to a more positive environment inside the cell and this is just going to continue and propagate its way all the way down the axon now this is going to be followed by potassium channels opening up which is going to cause what we call our repolarization which is essentially resetting that charge back to be negative inside the cell and ultimately some other processes are going through there to rebalance out our electrolytes - the same configuration that we had when we started and so this is essentially how we get a signal from the neuron body down the axon to the end and so essentially that is gonna lead us into talking about the next thing here that I want to talk about which is our neuromuscular Junction and this is essentially where the axon is terminating into a motor endplate on some sort of muscle and this is really where all the action is going to take place here so here again we have that depolarization taking place and this charge is making its way down the axon and once this action potential reaches the end here what we call the axon terminal what's gonna happen is we're gonna trigger these calcium voltage-gated channels these channels are gonna open up and allow calcium inside of the axon terminal now also within the axon terminal we have these vesicles here and essentially these vesicles have the neurotransmitter acetylcholine inside of them and so when we have this calcium enter into this part of the neuron that this is actually going to allow these vesicles to go down and attach to the base of our membrane and this is going to release the acetylcholine into this gap junction and so then now this acetyl choline is going to diffuse across this synaptic cleft and they're gonna bind to these acetylcholine receptors and by binding to these receptors these are actually sodium gated channels and once the cetyl choline binds they open up allowing sodium to enter into the muscle cell which is going to lead to depolarization of this cell and that's essentially how we get a signal from one of our motor neurons initiated in the neuron body to propagate or depolarize down that axon through the axon terminal and ultimately pass that signal along to a muscle cell depolarizing it essentially causing the contraction that we're wanting to see now after all this is said and done there is an enzyme something that we call acetylcholinesterase that is going to break down the acetylcholine making it available to eventually go back in and form new vesicles within that axon terminal and this is a pretty good down and dirty review of the anatomy and physiology that goes into this neuron action potential ultimately leading to the contraction of muscle cell but it's this spot here which is where we're gonna see the effect of the paralytic or the neuromuscular blocking agents that we're going to talk about actually in the next lesson but it really helps to have this understanding of what's happening here at the cellular level to be able to understand how these medications are actually achieving the blockage of contraction that we're hoping to see and it will also help to explain one of the major differences between two of the big classes and medications and so again hopefully this explanation here will give you that good understanding that you need to understand what's happening with those medications when we talk about those in that next lesson all right and so that's gonna wrap up this lesson here we started this series off here talking about really what are our paralytics or neuromuscular blocking agents why is it that we're using them and then ultimately how is it that they are having their effect and all of that is through interference in this process that we have of this neuron motor neuron action potential leading to that muscle contraction I hope that so far the stuff made sense for you guys and that you were able to get some good information out of this lesson and so as always I want to thank you guys so much for watching if you found the lesson useful head down below leave us a like leave us a comment or subscribe to our channel if you haven't already make sure and also check us out on Facebook and stuff and Twitter as well as check out another one of our awesome videos right here thank you guys so much for watching you have a wonderful day